has part has part has_part has quality has quality composed primarily of vadose zone phreatic zone rock soil clay aquifer https://en.wikipedia.org/wiki/Aquifer EcoLexicon:aquifer envoPolar SWEETRealm:Aquifer An underground layer of water-bearing permeable rock or unconsolidated materials (gravel, sand, silt, or clay) from which groundwater can be usefully extracted using a water well. mud silt gravel solid layer porous